The general objectives of the Hypertension SCOR program at Boston University are to elucidate the role which humoral factors play in the pathogenesis, treatment, and vascular complications of hypertension. The various forms of experimental and human hypertension will be characterized according to their endocrine, renal, and hemodynamic aspects. New adrenal hormones which could influence blood pressure will be examined in man and experimental animals. The role of the renin-angiotensin system and its interrelationships to sodium, cardiac function, and regional blood flow will be studied in man and animal models utilizing competitive antagonists of angiotensin and converting enzyme inhibitors. In addition, the mechanisms for low-renin and high-renin hypertension will be examined according to their relationship to mineralocorticoid hormones, adrenergic function, carbohydrate tolerance, renal function, age, race and response to antihypertensive therapy. The development of atherosclerosis will be studied in a number of hypertensive animal models. The effects of well-known or potential risk factors as hyperlipidemia, carbohydrate intolerance, obesity, and renin status on arterial morphology and metabolism will be evaluated. Cultured vascular smooth muscle cells and microvessel preparations will be utilized to assess the influence of vasoactive agents, hormones, and antihypertensive drugs on their metabolism. In addition, measurement of plasma renin activity will be made in patients with prior myocardial infarction to obtain information of the role of the renin-angiotensin system in the development of vascular disease.